PyCloudStack run failed with log "'VMGuest' object has no attribute 'tsx'"

[Zheng, Qi]

Tried example Operate VM via Libvirt but failed with log below.

Traceback (most recent call last):
  File "./start_vm.py", line 14, in <module>
    inst = vm_factory.new_vm(VM_TYPE_TD, auto_start=True)
  File "/home/zhengqi/.local/lib/python3.6/site-packages/pycloudstack/vmguest.py", line 400, in new_vm
    diskfile_path=diskfile_path, cpu_ids=cpu_ids)
  File "/home/zhengqi/.local/lib/python3.6/site-packages/pycloudstack/vmguest.py", line 91, in __init__
    self.vmm = vmm_class(self)
  File "/home/zhengqi/.local/lib/python3.6/site-packages/pycloudstack/vmm.py", line 143, in __init__
    self._xml = self._prepare_domain_xml()
  File "/home/zhengqi/.local/lib/python3.6/site-packages/pycloudstack/vmm.py", line 175, in _prepare_domain_xml
    self.set_cpu_params_xml(xmlobj)
  File "/home/zhengqi/.local/lib/python3.6/site-packages/pycloudstack/vmm.py", line 222, in set_cpu_params_xml
    if self.vminst.tsx is False:
AttributeError: 'VMGuest' object has no attribute 'tsx'

I installed the pycloudstack by pip3 install --user pycloudstack.
BTW, install from source was failed, asking for 'setup.py'.

cd ~/pycloudstack
pip3 install --user --upgrade .